Megaplex-4Next-Generation Multiservice

Access Node

SecFlow-1vRuggedized Industrial IoT Gateway

Many public utilities still employ various types of legacy equipment within their operational technology (OT) network. These devices have been in use for decades and utility networks rely on their proper functioning for mission-critical operations. Remote telemetry units (RTUs), for example, are deployed in thousands along utility lines and in remote sites, and they all need to communicate with the control room with 24x7x365 availability. A sizable portion of them are doing so using good old analog dial-up modems over public switched telephone network (PSTN) services that are leased from a local telco.

PSTNs are another relic. They are very costly to maintain and don’t meet today’s service requirements and new technologies. Telcos are therefore quickly terminating them, if they haven’t done so already, leaving PSTNs’ remaining users without a proper solution to ensure immediate service continuity that doesn’t involve uprooting their entire network.

Application Brief

PSTN Replacement – The Easy Way

What to do when your service provider turns off your legacy connections

Application Brief What to do when your service provider turns off your legacy connections

RAD has the ideal solution that allows utilities to keep their current equipment fully operational – both at the end

points and network center. They need not be affected by telcos’ decision to retire older connection services, and

migrate to newer generation RTUs at the pace that is right for them.

This is how RAD’s solution works:

1. The RTUs are connected to RAD SecFlow-1v gateways via a serial link.

2. The SecFlow-1v emulates a PSTN connection when sending or receiving RTU data to and from the control center

over the new packet-switched network (PSN).

3. At the center, a Megaplex-4 multiservice access gateway replaces the previous stack of dial-up modems to collect

and send the data to and from all remote end points and transmits it to the terminal server and SCADA master.

4. The operation of RTUs, terminal server and SCADA master remains unchanged – as far as these devices are

concerned, they are still connected using the PSTN.

5. The next migration step would be to embed the terminal server within the Magaplex-4 so that the services continue to run unaffected without relying on discontinued equipment.

Seamless PSTN Replacement – Solution Overview

Features and Benefits

• Seamless migration by emulating analog dial-up modems and AT commands.

• Preservation of installed RTUs and main terminal server, supporting any type of remote site equipment

(serial, embedded PSTN, Ethernet, I/O).

• Secure end-to-end tunneling over public PSN.

• Central management system to manage up to thousands of remote sites, with zero-touch provisioning (ZTP)

and remote lifecycle management.

• Cost and footprint savings by replacing multiple small modems and terminal servers with a single aggregation

device

www.rad.comSpecifications are subject to change without prior notification. This document contains trademarks registered by their respective companies. SecFlow-1v and Megaplex-4 are trademarks of RAD Data Communications Ltd. The RAD name and logo are registered trademarks of RAD Data Communications Ltd.

RADviewRTU

RTU

Serial

Serial

IPAT + Cal no.

PacketNetwork

RADview

SCADAMaster

Megaplex-4

TerminalServer

Serial

RTU

RTU

SecFlow-1v

SecFlow-1v

Serial

Serial IPAT + Cal no.

Megaplex-4

PSTN

RADview

SCADAMaster

Analog ModemsTerminalServer

Serial

RTU

RTU

Serial

Serial IPAT + Cal no.

Analog Modem

Analog Modem

Current Network

New Network – Phase 1

New Network – Phase 2SecFlow-1v

SecFlow-1v

Embedded TerminalServer Emulation

PacketNetwork SCADA

Master

Application Brief What to do when your service provider turns off your legacy connections

The following diagram illustrates the “before” and “after” of PSTN replacement:

To learn more about seamless PSTN replacement and other RAD solutions, contact us at market@rad.com